Abstract

Large Stokes-shift four-wave mixing is generated in a deeply normal dispersion regime from a 20 cm commercial large-mode-area photonic crystal fiber pumped by amplified femtosecond pulses. The phase-matching condition is realized through an intermodal scheme involving two pump photons in the fundamental fiber mode and a pair of Stokes/anti-Stokes photons in a higher-order fiber mode. Over 7% conversion efficiency from the pump input to 586 nm anti-Stokes signal has been attained.